Various manufacturers produce HVAC systems, such as rooftop units (RTUs), capable of complying with the “two-speed” regulations for blower speeds that some require for certain HVAC systems. The multi-speed HVAC systems provide conditioning flexibility and reduce power consumption. Some customers, however, have existing single speed systems that are not due for replacement in the near future. Existing customers can wait for twelve to fifteen years before their HVAC system is worn out to justify the installation of a new system. During this time, the customers are unable to take advantage of improved HVAC systems and the energy saving operation of products such as a Multi-Stage Air Volume (MSAV) product.